feat: info icon

frontend/index.html

@@ -86,7 +86,11 @@
   <div id="map" class="d-none d-md-block"></div>
   <div id="card-container" class="shadow-lg bg-success-subtle">
     <h1 class="fs-4 text-center m-2 mb-4">Klangkarte
-      <a class="small text-decoration-none" title="Info" href="" onclick="return showNotice('info')">?⃝</a>
+      <a id="info" class="text-decoration-none" title="Info" href="" onclick="return showNotice('info')">
+        <svg>
+          <use href="/icons.svg#info"></use>
+        </svg>
+      </a>
     </h1>
     <div id="cards">
       <div id="card-template" class="card shadow-sm">